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A359431 a(n) = A325973(n) - A326043(n).

%I A359431 #8 Jan 04 2023 14:38:13
%S A359431 0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,4,0,0,2,0,0,0,0,5,0,0,
%T A359431 0,3,0,0,0,6,0,0,0,0,0,0,0,8,0,0,0,0,0,6,0,8,0,0,0,0,0,0,0,12,0,0,0,0,
%U A359431 0,0,0,16,0,0,0,0,0,0,0,12,12,0,0,0,0,0,0,12,0,0,0,0,0,0,0,20,0,0,0,10,0,0,0,14,0
%N A359431 a(n) = A325973(n) - A326043(n).
%H A359431 Antti Karttunen, <a href="/A359431/b359431.txt">Table of n, a(n) for n = 1..65537</a>
%o A359431 (PARI)
%o A359431 A325973(n) = (1/2)*sumdiv(n, d, d*(issquarefree(d) + (1==gcd(d, n/d))));
%o A359431 A326043(n) = if(1==n, n, my(f = factor(n)); prod(i=1, #f~, floor((1/f[i, 2]) * ((f[i, 2]-1) + (((f[i, 1]^(1+f[i, 2])) - 1)/(f[i, 1]-1))))));
%o A359431 A359431(n) = (A325973(n)-A326043(n));
%Y A359431 Cf. A048107 (positions of 0's), A325973, A326043, A359471.
%Y A359431 Cf. also comments in A325981.
%K A359431 nonn
%O A359431 1,16
%A A359431 _Antti Karttunen_, Jan 04 2023